This invention relates generally to underwater diving, and more particularly to apparatus for propelling a diver underwater.
Underwater diving is a popular activity. One common diving method is SCUBA diving (named for Self-Contained Underwater Breathing Apparatus), in which a diver is provided with a portable tank containing compressed breathable gas. The gas is metered to the diver through a regulator. Another type is breath-hold diving in which the diver uses his own lung capacity while swimming underwater.
It is often desirable to cover more distance underwater than a diver could cover solely by swimming with his limited lung capacity or breathing gas supply. It is known, for example, to provide a thruster or diver propulsion unit which pushes or pulls a diver through the water using a propeller powered by an electric motor connected to an electrical power supply.
It is also known to extend a diver's range with an underwater glider. An underwater glider has wings that create a drag force and enable a diver to travel horizontally a substantial distance while rising or falling in a body of water. Known underwater gliders are complex, and therefore have the potential for failure. Known gliders require electrically-powered controllers, or require a diver's air supply and therefore cannot be used for breath-hold diving. These devices are also expensive and can be noisy and send out electrical signals that can be disturbing to marine life.
Accordingly, there is a need for an underwater glider that is mechanically simple and is suitable for both SCUBA diving and breath-hold dives.